There is in existence, a variety of battery powered equipment and industrial machinery which utilize commercial storage batteries. Such equipment is often utilized in areas where other sources of power are not available or not suitable. For example, in many mines it may not be appropriate to use internal combustion engines because the engine exhausts render the area in which miners are working unsafe. At the same time, the availability of electric power lines is limited and in any event the connection to power lines could limit the mobility of electric powered equipment.
However, if in those instances where battery powered equipment is utilized, it is, of course, necessary to provide some capability for recharging the batteries. It should be understood, that the personnel available for this purpose are not skilled mechanics or service personnel, and in many instances battery charging must be accomplished in remote areas by untrained people.
It would be highly desirable, therefore, to provide a battery charging system which is easy to use, fully automatic, and which would require no field adjustments. At the same time, such a system should provide a complete battery charge regardless of initial battery conditions, charging line voltage and ambient temperature, and should insure proper operation without the necessity for trained personnel to set up the system or to make necessary adjustments and connections.